Improved machine for cutting screws



N. PETERS, PHOTO-LUNOGRPHER, WASHINGTON D C UNITED STATES PATENT OFFIC..

JOHN A. MERRIMAN, OF CHICAGO, ILLINOIS.

IMPROVED MACHINE FORCUTTING SCREWS.

Specilication forming part of Letters Patent No. 49,133, dated August 1, 1865.

section of myinvention. Fig. 2 is a transverse vertical section of the same, the plane of section being indicated by the line a z, Fig. 1, and looking in the direction of the arrow marked near that line. Fig. 3 is a perspective view of the ring or cylinder, showing its internal ways or bearings. Fig. 4 is a front elevation of the cap or face plate. Fig. 5 is a side elevation of the same. Fig. 6 is a front elevation ot' the sliding tlange, with its levers and rockshaft attached. Fig. 7 is a side elevation of the same. Fig. S is a side elevation of the dieholder, with its levers shown in perspective. Fig. 9 is a front elevation of the same. Fig. 10 is a side elevation of the die. Fig. 11 is a front elevation of the same. Fig. l2 is a front elevatvion of the tapholder. Fig. 13 is a longitudinal vertical section ot' the same. Fig. 14 is aback elevation of the same. Fig. 15 is a side elevation of the latch. Fig. 16 is a front elevation of the same. s

Similar letters of reference indicate like parts.

This invention consists in a ring or cylinder provided with internal Ways or bearings, portions of which are made eccentric, in combination with a set of levers attached to the dieholder, a set of dies provided with an inclined plane and a projection or hook, a sliding flan ge with its connecting andoperatin g levers, and a latch or stop, in such a manner that by working the operating-lever thc sliding flan ge, with the ring or cylinder attached, is moved backward and forward, which causes the dies to open l and close at the will ofthe operator, which allows of the bolt being Withdrawn without stopping or reversing the machine.

By changing the position ofthe ring or cylinder in relation to the sliding tlan ge the size of opening in the dies can be adjusted to compensate for wear in the dies, or t-o cut bolts of different sizes. By raising the latch and thus permitting the sliding flange to move a trifle t farther backward the dies are all relieved, and can readily he taken out or changed.

A represents a frame, made of cast-iron or other suitable material, and provided with two guideways, a, to receive the movable head-` block B. In this head-block the bolts are fastened to which a screw-thread is to be-cut.

C is the spindle which carries thehead D` containing the dies. Said spindle has its bearings in two standards, c, rising from the frame A, and it is provided with a hand-wheel or pulley, cl, by means of which a rotary motion can be imparted to it.

The head D is composed of seven distinct parts, which are connected to each other and to the spindle, as will be presently explained. The inner part or die-holder, e,is rigidly attached to the-spindle with asetscreW or inlany other suitable manner, and is provided with three (more or less) slots, f,to'receive the dies g. These slots f meet or runinto other slots It, runnin g back the entire thickness of the dieholder c, and are at right angles with its face. In these slots h, working on suitable fulcrums, are arranged the levers z'. (See Fig. S.) In the rear of the die-holdere is the angej, made to i slide ou the spindle C, hutmade to rotate with it by means of the feather j and the slot jz.

ln front of the flangej, andlirmly fastened to it by means ot' bolts j3 passing through slots ji, (see Fig. 6,) is the ring or cylinder k. `(See Fig. 3.) This ring or cylinder is provided with three internal ways or bearings, la k2 7c3. These Ways or bearin gs are subdivided into six (more or less) equal parts, the number otparts being twice the number of dies used. `Ijlach alternate part is made on the same circle with the ring or cylinder. Theremaining parts .are`

made eccentric with the ring or cylinder. The

eccentric parts ot' the Ways or bearings k' and k2 are inthe same position to each other and expand in the same direction with each other.

used only to adjust the size of opening in the dies and to compensate for wear.

The dies g are retained in the slots f by means of a cap or face plate, l, (see Figs. 4 and 5,) which is secured to the die-holder e by screws l. This cap or face plate l has a flange or projection, m, at its periphery, which shuts over a portion of the ring or cylinder, thereby excluding the chips from the working parts of the machine.

Through the flange m are openings u, corresponding to the number and position lof the slots j' in the die-holder e. Through these openings nthe dies are passed when it becomes necessary to remove or change them.

The sliding iiangej is moved backward and forward by means ot' the forked lever o, (see Figs. 6 and 7.) the rock-shaft o', and the operating-lever o2, as will be readily understood.'

This arrangement of levers may be varied to suit dil'erent styles of machines.

A portion of the outer ends of the dies g is made square or at right angles with their face, and a portion is made at an angle less than a right angle with their face. The latter portion forms an inclined plane, which is prolonged beyond the back side of the die and forms a projection or hook, g. The altitude of this inclined plane should correspond with the amount of movement required in opening and closing the dies. I do not wish to be understood, however, as coniinin g myself to the exact proportions of the inclined plane, which may be varied according to circumstances. The inner ends of the diesg are so made as to form screwcutting tools, which act upon the iron rod or bolt and cut a screw-thread thereon. When the dies g are in the position for working,Fig.

1, the projections g rest upon the ends ofthe levers i, and the square part of their outer ends bear firmly against the way or hearing k3 in the ring or cylinder k.

The latch or stopp (see Figs. 15 and 16) is attached to the standardcby means of a screw,

'p'. This latch or stop prevents the langej from sliding too far back and loosening the dies while the machine is in motion. The exact form of this latch may be varied to suit circumstances. When the flangej, with the ring or cylinder 7c attached, is moved backward by means of the operating-lever o3 the internal way or bearing, k2, in the cylinder 7c comes in contact with the levers fi, and thereby causes them to act upon the dies g and draw them outward. The bearing k2 does not reach the y levers i until the bearing k3 has left. the square portion of the dies g. lt (the bearing k3) then recedes along the inclined portion and perlnits \\the dies g to he drawn outward or expanded.

When the bearing 7c3 has reached the point in the incline where the projection or hook g begins it is arrested in its further progress by the latchor stop p.

Whenever it becomes necessary to remove the dies g, the latch p is raised or removed and the sliding\lange j, with the cylinder la attached, is permitted to move backward until the bearing k3 clears theprojection or hook g. The dies g are then taken out at the openings n in the iiange m of the cap l. When the ange j, with the ring or cylinder 7c attached, is moved forward by means of the operating-lever O2,

the way or bearing kf in the cylinder 7c comes in contact with the inclined Yplanes at the ends of the dies g and forces them inward until it reaches the square part, when it ceases to act upon the dies, but continues its forward movement until it reaches the cap l, in which position the square part of the ends of the dies g bears firmly against it (the way 7c3) and is capable of resisting the pressure consequent upon cutting the holt without yielding.

The position of the ring or cylinder k and consequent size of opening in the dies while the machine is cutting the screw may be regnlated by means of -the circular slots jt, through which the boltsj3 pass, which allows of the ring or cylinder 7c being moved in either direction and fastened in the desired position.

The outer or long ends ot' the levers i are slightly curved, so as to give to the inner or short ends a uniform motion. This becomes necessary owing to the continually-increasing distance from the fulcrum to the point where the bearing 7a2 acts upon the levers After the bearing k2 leaves the levers z' in its forward movement, the outer ends of the levers i rest upon the bearings k. This holds the dies in their proper position against the bearing k3 and prevents any lost motion.

The tap-holder q* (see'Figs. 12, 13, and 14) is made to lit the central hole, q, in the faceplate l, and is provided with aflange, q', which bears against the .face-plate l. It is also provided with a stud, q2, which passes through the face-plate l in the notch g3 and enters one of the die-slotsf in the die-holder e, the dies being removed. The notch g3 being narrower than the slot f, the stud q2 locks by the faceplate Z. By this means the tap-holder is held firmly in its position. The tap-holder is also provided with a square hole or socket, c, in its center, in which the shank of the tap tits while in use.

The operation of this machine is as follows: The several parts being in their position, as shown in Fig. 1, the motive power is applied to the spindle O, causing it, with the head lD and dies g, to revolve around a common center. The bolt upon which a screw-thread is to be cutis fastened in the movable head-block B, which is moved up to the dies, causing them to cnt the required screw upon the bolt. When the screw has been cut the desired length npon the bolt the operator, by means of the operating-lever 02, causes the flange, j, with the cylinder 7c attached, to slide backward upon the spindle C, and the bearing k2 acts upon thelevers t', and the levers, acting upon thedies g, cause them to be drawn outward or opened,

which allows of the bolt being withdrawn withn out stopping or reversing the machine. By

moving the flange j, with the cylinder 7c attached, forward the Way or bearin g la is made to act upon the incline ofthe dies g, and causes them to be pushed inward or closed. The machine is then ready to receive another bolt.

Havin gthus minute] y described the construction and operation of my invention, I do not wish to be understood as confining myself to this particularconstruction of all the parts; but, believing the sliding bearings, acting directly upon screw-cutting dies by means of machines for the purpose of closing them, to be new,

I desire to claim, broadly- 1. Closing dies by the use of the laterallyslidingT bearings k, acting directly upon the dies by means of inelines, operating substan` tially as and for the purposes herein specified.`

the sliding bearings 7c and the dies g, substani tially as herein shown and described, for the purpose set forth.

JOHN i A. MERRIMAN.

Witnesses: I

WARREN F. DAY, M. B. PAGE. 

